Combination brake and vehicle assembly

ABSTRACT

A disc brake construction adapted for use on front or rear wheels of motorcycles and the like. An annular disc having opposed bearing surfaces is supported for rotation within the wheel but on and coaxial with the axle of the wheel. Braking forces are applied through brake shoes that are oppositely aligned on opposite sides of these braking surfaces. The braking shoes are actuated by a hydraulic caliper that is supported by an annular drum coaxial with the axle. Devices are provided for absorbing reaction forces upon braking without transmitting these forces to the fork supporting the axle.

United States Patent 1 [111 3,899,049 Martin Aug. 12, 1975 41COMBINATION BRAKE AND VEHICLE ASSEMBLY Thomas C. Martin, 185 DevonshireSt., Boston, Mass. 02110 Filed: Nov. 27, 1973 Appl. No.: 419,336

Related US. Application Data Continuation of Ser. No. 233,962, March 13,1972, abandoned, which is a continuation-in-part of Ser. Nos. 61,258,Aug. 5, 1970, and Ser. No. 849,312, Aug. 12, 1969, abandoned.

Inventor:

[56] References Cited UNITED STATES PATENTS 3,602,339 8/1971 Sontheimer188/18 A 3,757,883 9/1973 Asberg 188/18 A 105 a7 n so as m FOREIGNiPATENTS OR APPLICATIONS 346,777 7/1'960 Switzerland 188/18A PrimaryExaminerGeorge E. A. Halvosa Attorney, Agent, or F irmWolf, Greenfield &Sacks [5 7 ABSTRACT A disc brake construction adapted for use on frontor rear wheels of motorcycles and the like. An annular disc havingopposed bearing surfaces is supported for rotation within the wheel buton and coaxial with the axle of the wheel. Braking forces are appliedthrough brake shoes that are oppositely aligned on opposite sides ofthese braking surfaces. The braking shoes are actuated by a hydrauliccaliper that is supported by an annular drum coaxial with the axle.Devices are provided for absorbing reaction forces upon braking withouttransmitting :these forces to the fork supporting the axle.

I l Claims, 13 Drawing Figures PATENTEB AUG 1 2 1975 COMBINATION BRAKEAND VEHICLE ASSEMBLY CROSS-REFERENCE TO RELATED APPLICATIONS This is acontinuation of application Ser. No. 233,962 filed March 13, 1972, nowabandon, which is a continuation-in-part of application Ser. No. 61,258filed Aug. 5, 1970; and application Ser. No. 849,312 filed Aug. 12, 1969now abandoned.

BACKGROUND OF THE INVENTION Although most motorcycles in use today usemechanically operated braking means, several have introduced the use ofdisc brakes. This development is due in part at least to the increasedhorsepower and consequent higher average speeds at which motorcyclescurrently operate. These disc brakes, however, have been used only onthe front wheels of the cycles. Moreover, these braking systems use asingle disc that is located externally and to one side of the wheel hub.Since the plane of the disc brake surface upon which braking forces areapplied in such brakes is substantially closer to one end of the hubthan the other, there is a tendency for the wheel to pull toward oneside upon application of braking forces at speed. This pulling creates apotentially dangerous physical imbalance or lateral instabilityespecially at high speeds. Such arrangements also appear to result intorque and loading imbalances that are absorbed by one of the legs ofthe motorcycle front fork. This torque imbalance includes a componentabout an axis normal to the axle of the wheel. The loading imbalanceincludes side forces generated by piston reaction that are transmittedto the leg of the fork. Such difficulties or limitations may havecontributed to the limited use of disc brakes to the front wheels ofmotorcycles. In addition, the disc brakes heretofore in use are ratherbulky and cannot fit readily into the rear wheel area which must alsoaccommodate the drive mechanism.

SUMMARY OF THE INVENTION It is an object of the present invention toovercome the deficiencies of the prior art referred to above and in mycopending application. In the present invention, there is provided abrake structure which is designed for use in either or both of the frontand rear wheels of motorcycles and like vehicles. In this arrangement,the disc brake assembly is arranged with a hub supported on an axlehousing and including a support member that extends annularly about theaxle housing of the wheel. Bearing surfaces are formed on an annulardisc integral with the support member. A caliper system having a pair ofbrake shoes is supported within the hub of the assembly in alignmentwith the bearing surfaces. The caliper system is supported on a calipersupport drum which is coaxial with the axle housing and which providesmeans for absorbing the side forces effected upon application of thebraking force without transmitting these side forces from the drum tothe fork of the vehicle.

It is thus an object of the present invention to provide a compact brakestructure designed for use with either the front or rear wheels of amotorcycle or like vehicle, but particularly useful for rear wheels ofmotorcycles. This brake structure is adapted to be incorporated withinthe hub of the wheel providing a compact, efficient braking system thatis protected from contamination by oil, grease and the like. A furtherobject of the present invention is to provide a brake structure withinthe hub of the wheel in which the side forces resulting from theapplication of braking forces on the disc are absorbed totally by acaliper support drum that does not transmit these forces to the fork ofthe cycle.

One further object of the present invention is to provide an improvedand balanced brake structure in which braking action is effected byfrictional engaement of brake pads and discs simultaneously in a pair ofparallel planes spaced closely to and on opposite sides of a centralplane passing normally through the wheel axis.

A further object of the present invention is to provide means foradjusting the brake shoe to accommodate for wear on the brake pad. Afurther object of the present invention is to provide an improved meansfor retracting the brake shoe from braking engagement after removal ofthe hydraulically applied forces of braking.

A further object of the present invention is to provide a simple andeffective means for adjusting both the primary and secondary brake padsof a caliper system in a floating caliper system.

One further object of the present invention is to provide an improvedcaliper system of the floating caliper type that includes a positivemeans for retracting the primary and secondary brake pads to assureproper clearance between discs and pads.

A further object of the present invention is to provide an enclosed discbrake system that protects the operational components of the system fromexternal contamination and damage while at the same time providingeffective cooling means and adequate drainage for moisture andcondensation within the system.

One more object of the present invention is to provide means forvisually indicating the need for brake pad replacement on both theprimary and secondary brake shoes.

A further object of the present invention is to provide an improvedbrake means that includes brake shoes supported on a caliper by guidepins. The guide pins permit parallel displacement of the brake shoes inopposite directions by pistons and return springs and partially absorbbrake torque reaction.

One further object of the present invention is to provide a brake systemfor motorcycles which is adaptable to an arrangement in which brakingforces for front and rear wheel brakes may be applied uniformly,simultaneously, and from a single source, thereby providing a faster andsafer deceleration. The arrangement also provides a basis forincorporation of a fail-safe, splitbraking system, the use of brakingratios and a servo system.

The present invention provides a disc brake system having two pairs ofopposing pistons that permit the use of larger brake pads and thereforeprovide a more effective use of the radial contact area of the disc.

Another object of the present invention is to provide an improvedbraking system that is simple and inexpensive to maintain and repair.

Another object of the present invention is to provide a braking systemwhich has adequate means for cooling including means for isolating thebrake disc from the axle area to minimize heating of the wheel bearingsand cooling vents in the hub web for heat dissipation.

Another object of the present invention is to provide tool means forsimultaneous adjustments of brake pads for pad wear. One further objectis to provide a means for permitting positioning of the disc brakecaliper other than in lateral alignment with the fork for designexpedience without the need of supplemental supports.

Another object of the present invention is to provide an improved brakesystem that is. adaptable for the front and and rear wheels of anyconventional motorcycle either as original or replacement equipment.Such equipment may be incorporated with no modifications or replacementsof the existing motorcycle components.

DETAILED DESCRIPTION OF THE DRAWINGS The foregoing objects andadvantages of the present invention will be more clearly understood whenconsidered in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan elevational view of a preferred embodiment of theinvention as incorporated in the rear wheel of a motorcycle;

FIG. 2 is a fragmentary, cross-sectional elevation taken substantiallyalong the line 2-2 of FIG. 1;

FIG. 3 is a fragmentary, partially broken away elevation takensubstantially along the line 3-3 of FIG. 2, with the face plate andcollar removed;

FIG. 4 is a fragmentary, cross-sectional elevation taken substantiallyalong the same line as FIG. 2 but illustrating a modification of theinvention;

FIG. 5 is a cross-sectional detail of the embodiment of FIG. 4 takensubstantially along the line 5-5 of FIG.

FIG. 6 is a cross-sectional detail of the embodiment shown in FIG. 4taken along the line 6-6 of FIG. 4;

FIG. 7 is a cross-sectional detail taken essentially along the line 77of FIG. 3;

FIG. 8 is a fragmentary, elevational view taken along the line 8-8 ofFIG. 7;

FIG. 9 is a plan, elevational view of a further modifi cation of theinvention as embodied in the front wheel of a motorcycle;

FIG. 10 is a cross-sectional, fragmentary view of the embodiment of FIG.9 taken substantially along the line 10-10 of FIG. 9;

FIG. 11 is a cross-sectional detail taken along the line 11-11 of FIG.4;

FIG. 12 is a fragmentary detail taken along the line 12-12 of FIG. 11;and

FIG. 13 is a partial, cross-sectional elevation of a tool necessary toadjust the threaded shafts to compensate for brake pad wear and toprovide proper clearance between pads and disc.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1,there is illustrated the rear wheel 1 of the motorcycle. This rear wheelgenerally comprises a tire 2 that is mounted on the rim 5 of themotorcycle and supported by conventionally arranged spokes 4, that inturn are secured to the wheel hub 3. The wheel 1 is supported on therear axle 6 which in turn is supported at opposite ends by the parallellegs 7 of the motorcycle swing fork. The axle 6 is secured againstrotation by suitable means. Coaxial with the axle 6 is a sprocket 8around which extends the motorcycle chain 9 that in turn is connectedconventionally by means not shown to a drive source.

A support member 11 is rigidly secured to the sprocket 8 by a pluralityof bolts 12 that extend through the sprocket 8 and into the supportmember 11. The support member 11 is provided with an annular core 13that is coaxial with the axle 6. integrally formed with the core 13 is acoaxially formed and arcuately flared wall member 14. A projecting bossportion is also integral with the wall member 14 and annular core 13.The bolts 12 extend into the boss portion 15 which is sufficientlymassive to provide a sturdy support and means for securing the hub tothe sprocket 8. The wall member 14 is formed with a plurality ofradially extending ribs 16 that extend outwardly from the boss member 15and provide added cooling and strength to the wall member 14. Inaddition, a series of ribs 17 extend between the annular core 13 and thewall member 14 at the juncture of their inner surfaces. Preferably inthe order of six to eight ribs 16 and 17 may be provided, depending uponthe specific design contemplated.

The annular core 13 is supported and spaced in relation to the axle 6 bymeans of ball-bearing race assemblies 18 at spaced positions along theaxle 6. In FIG. 2, only one of such ball-bearing races is illustrated. Asecond ball-bearing race is located at the left end of the axle6 asviewed in FIG. 2. The inner races of the wheel bearings are fixed, theouter races are rotatable. An opening 19 in the wall member 14 isprovided for ready access to the interior 20 of the wheel hub forpurposes of bleeding the brakes or adjusting the pads for wear.

The crown 21 of the hub is integrally formed with the outer periphery ofthe wall member 14, and this crown conventionally provides a pair ofparallel, annular flanges 22 having a series of holes 23 to which thespokes 4 of the wheel may be attached. Also conventionally provided area plurality of cooling fins 24. Spaced parallel to one another andparallel to the axle 6 are a series of integrally formed ribs 25 on theinner surface of the crown 21. These ribs provide added support to thehub of the wheel. The ribs terminate at a shoulder portion 26, thusproviding a securing and locating means for the annular disc 27. Thedisc 27 is secured within the interior 20 of the hub by a series ofbolts 28 that extend through the disc and into the ribs 25. The disc 27is thus secured for rotation with the support member 1 l. Caliperelements 20 and 30 are secured within the periphery of the hub againstrotation and symmetrically on opposite faces of the disc 27 by a calipersupport drum generally illustrated at 30A. The caliper support drum 30Ain turn is fixed between the inner ends of the rotatable ribs 17 and afixed face plate 31 that is also coaxially mounted on the axle 6. Thecaliper support drum consists essentially of a pair of annular wallmembers 32 and 33. Each of these wall members have flanges at adjacentends that face oneanother. These annular flanges are rigidly securedtogether by a series of bolts 36. The flanges 34 and 35 are preferablyessentially coplanar with the disc 27. Integrally formed with theflanges 34 and 35 is the yoke assembly 37. This yoke assembly 37includes bracket elements that support respectively the elements 29 and30. The yoke 37 provides sufficient clearance for the inner edge of thedisc 27 and also provides support for each of the elements 29 and 30respectively on opposite sides of the disc 27. Conventional brake pads38 and 39 are supported in facing relation with opposite surfaces of thedisc. and are connected to brake shoes 40 and 41 in turn operated bypistons in elements 29 and 30 in a manner consistent with the structureillustrated in my copending application, Ser. No. 61,258 filed Aug. 5,1970, and entitled BRAKE MEANS.

The annular support members 32 and 33 are supported in spaced relationto the axle 6. The member 32 is supported in spaced relation from theannular core 13 by ball-bearing races 42. The outer race is fixed, theinner race is rotatable. The races 42 are engaged between inner ends ofribs 17 and a shoulder 42A on the inner surface of wall member 32, Theannular support member 33 is provided with a splined end 43 that engagesan annular flange of face plate 31 which has an outer surface forming asplined portion 44 and secures the caliper support drum 30A againstrotation. The drum 30A is thus supported at one end by races 42 and atthe other by shoulder 45.

The face plate 31 is provided with a shoulder 45 at its inner peripherythat butts a collar 46. The collar 46 is coaxial with the axle 6 andengages the inner surface of the annular support member 33 to preventits misalignment during assembly of the face plate 31.

The face plate is provided with a pairof cooling manifolds 47 similar tothat shown in the previously mentioned copending application. Alsoprovided is a torque take-up 48 and connecting rod 48A of conventionaldesign. The torque take-up 48 precludes the face plate from rotatingwhen the brake is activated.

A weep hole 31A in the face plate 31 provides means for egress ofmoisture which may have collected by condensation or otherwise withinthe unit.

As illustrated in FIG. 3, the flanges 35 and flange 34 behind it may beprovided with access ports 49 for servicing the element 29 from theright side of the assembly as viewed in FIG. 2. The honeycomb ribbingillustrated in FIG. 3 is provided on the flanges 34 and 35 at 50 forpurposes of providing added strength to the caliper support mechanisms.Also, as illustrated in FIG. 3, apertures 51 are provided in the disc 27at the outer periophery between the portions of the disc that is securedto the ribs 25. These apertures permit the free passage of air forcooling purposes through the interior of the hub.

In the operation of the brake assembly illustrated in FIG. 1, therotating sprocket 8 normally drives and rotates the support member 11 asthe motorcycle is moving. When the brakes are applied, hydraulic fluidis introduced into the elements 29 and 30 simultaneously. These elementsare fixed. The elements thus are simultaneously actuated to move thebrake shoes and the pads carried by the shoes axially towards oneanother and into braking engagement with the opposite faces of the disc27. The forces effected through the brake pads on the opposed faces ofthe disc are opposite and balanced and are absorbed wholly by thecaliper support drum which in turn is fixed on the annular core betweenthe ribs 17 and the face plate 31. The legs 7 of the swing fork thus donot absorb the caliper side loads.

Turning now to the configuration illustrated in FIG. 4, there is shown amodification of the invention which is simpler in arrangement and whichutilizes a symmetrically located disc. In this arrangement, like numbersrefer to elements that are essentially the same as those described inconnection with FIG. 1. The annular support member 33 is provided with aseries, preferably four in number, of bosses 52 that extend inwardlyfrom the inner surface of the annular support member 33.

These bosses are spaced from but are near the splined end 55A of thesupport member 33. The face plate 31 is provided with an annular collar53 having a surface facing and spaced from bosses 52. A plurality ofsprings 54 are positioned between the facing surfaces of the collar 53and the bosses 52. These springs may be held in position by conventionalpin means, as illustrated, that are attached to bosses 52.

The springs 54 normally tension the annular members 32 and 33 to theleft, as viewed in FIG. 4, and away from the face plate 31. The splinedend 55A of the annular support member 33 is provided with a sliding fitarrangement with a corresponding splined end 55 in the annular collar 53of the face plate 31. The caliper support drum 30A is thus capable ofbeing moved under the influence of 54 springs 54 in a direction parallelto the axle 6, thus closing or opening the spaces 43A. Supported on theyoke 37 are the caliper elements 56 and 57. In the case of theembodiment of FIG. 4, however, the elements are not symmetrical and onlyone is powered. In this arrangement, the caliper arrangement is asliding caliper configuration in which the primary power provided inelements 56 and 57 is a slave or secondary, non-powered element. Element56 includes a piston 93A which engages brake shoe 39 while element 57includes a threaded shaft that engages brake shoe 38'. The primaryelement 56 and the secondary element 57 are supported in a mannersimilar to that described in connection with FIG. 1. In thisarrangement, however, the disc 58 is symmetrically located with respectto the interior 20 of the hub. In order to attain this, the ribs 25 onthe inner surface 21A of the crown are shorter. Supplemental ribs 25Aare provided on the opposite side of the disc 58. This arrangement maybe attained by providing cut-out segments in the disc 58 through whichthe ribs 25A may slide during the'assembly of the disc 58, and itsattachment to the ribs 25. The caliper support drum 30A is normallylocated in a position such that the brake pads 38 and 39 arjsymmetricalwith respect to the disc 58. This is attainedby securing the bearingraces 42 in a shoulder 61 at one end of the drum 30A against the tensionof spring 54. The snap ring supported in the groove that is annularlyformed in the outer surface of the core 13 holds races 42 in place whenthe drum moves to the right as viewed in FIG. 4. Movement towards theright-fis normally resisted by action of the springs 55 until :there isa positive displacement occasioned by the application of the brakingforces. Upon the application of braking power, the brake pad 39 is movedby primary power source, namely, element 56, into engagement with disc58. The resultant normal reaction causes the caliper to move axially inthe opposite direction bringing the secondary pad 38 into contact withthe other side. of disc 58. When the pad loads are equal, axial movementof the caliper ceases.

Referring now to the embodiment illustrated in FIGS. 9 and 10, onceagain similar numbers refer to corresponding elements to the componentspreviously described. The support member 62 comprises an annular core 63that is coaxial with the axle 6. Extending symmetrically from the corein a radial direction is the web 64. This web 64 is integral with thecrown 65. The crown 65 is flared outwardly and symmetrically from thefree end of the web 64 and is formed with flanges and cooling finssubstantially similar to those previously described. In thismodification, however, there is provided a series of r'idially extendingvents that are drilled or otherwise formed in the surface of the crowntowards the annular core 63 within and parallel to the sidewalls of theweb 64. These vents, which may vary in depth and in width as well asthickness, are designed to provide a cooling surface for cooling the webwhich carries and is in thermal contact with the bearing surfaces. Theinner surface 21A of crown 65 is tapered to permit water to run outthrough weep holes (not shown). The bearing surfaces 67 and 68 areannular members that are suitably secured in annular grooves on oppositesurfaces of the web 65. Since the web is preferably formed of aluminumand the bearing surface is of conventional material, more effectivecooling is possible. These bearing surfaces 67 and 68 are coaxial withthe axle 6. The annular core 63 is supported for rotation relative tothe axle 6 by wheel ball-bearing races 69 and 70. Conventional greaseretainers or end caps 71 are provided on opposite sides of theballbearing races 69 and 70. Aligned with the bearing surfaces 67 and 68are the caliper elements 72 and 73. These elements include hydraulicallyactuated pistons 72A and 73A which operate respectively the brake shoes74 and 75. Attached to these brake shoes 74 and 75 are the brake pads 76and 77 respectively. Actuation of the elements simultaneously will thuscause movement of the brake pads into frictional braking engagement withthe bearing surfaces 66 and 68. The elements 72 and 73 are eachsupported on caliper support members 78 and 79 respectively. The calipersupport members 78 and 79 include means suitably shaped and formed toengage and secure the caliper within the hub of the wheel. This meansincludes as an integral part of the assembly the face plates 80 and 81.These face plates are supported on the axle 6 against rotation. The faceplates may be secured for example directly to the legs of fork 82A, asillustrated by members 82 and 83. These members are intended to andpreclude rotation of the face plates and caliper. The face plates 80 and81 are provided with a core portion 84 and 85 that is coaxial with theannular core 63 and cooling manifolds 80A and 81A respectively. The coreportions are supported in spaced relation with the annular core 63 byball-bearing races 86 and 87, or by other suitable means, such asbushings. Bearing grease retainers 86A and 87A cover the inner sides ofthe races 86 and 87 respectively, and prevent possible grease leakageand keep dust and dirt from entering the bearings. Integrally formedwith the core portions 84 and 85 are webs 88 and 89 that extend radiallyoutwardly into engagement with the calipers 72 and 73. End caps 90 and91 provide a bearing surface. These caps are sandwiched between the faceplates and the fork legs (not shown). Nuts are threaded onto the ends ofthe axle 6 on the outer sides of the fork legs (not shown).

In the operation of this arrangement, the support member 62 rotates withthe front wheel while the elements 72, 73 and the related supportingelements including the caliper support members 78 and 79 remainstationary. Upon the application of a braking force, fluid is introducedinto the calipers to exert pressure on the piston, thus forcing thebraking pad 76 and 77 into frictional braking engagement with thebearing surfaces 67 and 68. The forces effected by this frictionalinterengagement are absorbed by the caliper drum.

Referring to the modification of details illustrated in FIGS. 1 l and12, there is shown the details of a floating 0r caliper brake. Theembodiment illustrated may be used in any floating or sliding caliperarrangement of the type herein described. FIG. 11, however, illustratesa specific embodiment in detail of the floating piston caliperconfiguration, as shown in FIG. 4, detailing the brake wear adjustmentmeans.

In this arrangement, the disc 58 is provided with bearing surfaces thatare frictionally engaged by the brake pads 38 and 39. These pads are inturn supported as previously indicated by brake shoes 38 and 39'respectively. The brake shoe 39 is moved laterally by the pistons 92A,93A contained within the hydraulic cylinders and cutlined at 92 and 93.The brake shoe 39 is normally tensioned to a retracted position by aspring 94 within recess 94A. The spring 94 has one end that engages ahook on the wall of the caliper (not shown) and the other engaging abracket 95 that is integrally formed with the brake shoe 39'.

The brake shoe 38' on the secondary or slave element is similarlytensioned in a retracted position by the spring 96 that has one endsecured to the bracket 97 and the other end secured to the hook 98 byhead 98A. The brake shoes 38' and 39' are supported relative to thesecondary element 57 by a pair of guide pins 99 at opposite ends. Theguide pins are secured by heads 100 at one end to the brake shoe 38'.The other end of the guide pins extends into a sleeve 101 that in turnis secured within an opening in the secondary element 57.

Lateral adjustment of the secondary brake show 38 for pad wear may beeffected by. adjusting the pair of threaded shafts 102 and 103. Thesethreaded shafts 102 and 103 are dimensionally substantially identical toand are aligned with the cylinders in the primary element 56. Thethreaded shafts 102 and 103 are threaded through the secondary element57. Flanges 102A and 103A of one end of each of these shafts 102 and 103bear on and engage a surface of the brake shoe 38' opposite the surfacethat engages the brake pad 38. The other end of these shafts 102 and 103have a knob or head 104 and 105 that is slotted or geared. These heads104 and 105 are also formed with recessed hexagonal holes 106, asillustrated in FIG. 12. Springs 107 and 103 are symmetrically supportedon the caliper element by bosses 109 and 1 10 respectively. These bossesare integrally formed with the caliper element 57 and secure one endeach of the springs 107 and 108. The other end of each of the springs107 and 108 engage respectively the heads 104 and 105. These springsthus secure the posts 102 and 103 against inadvertent loosening. Markers104A and 105A on the springs 107 and 108 respectively indicate a pointat which the brake pads must be replaced. This occurs when the outerface of the heads 104 and 105 reaches the markers 104A and 105Arespectively.

Adjustments to the secondary element for taking up wear on the brake pad38 requires simultaneous tightening of the posts 102 and 103 toprecisely equal amounts. In order to effect this equal tightening of theposts 102 and 103, a tool as illustrated in FIG. 13 is provided.

The tool illustrated in FIG. 13 is provided with two shafts 1 1 l and 112 that extend parallel to one another. The shafts are spaced apart sothat the holes 106 of the heads 104 and 105 may be simultaneouslyengaged by hexagonal ends 111A and 112A. The other end of the shafts 111and 112 are supported in the bracket 113 having reinforced ribs 116A.This bracket 113 also supports a gear train 115. The gears are spacedfrom the bracket 113 by spacers 121A on shafts, with shaft 119 securedat one end by washer 121. The gear train 115 includes gears 116 and 117that are engaged by central gear 118, and is keyed to and controlled forrotation by shaft 119. Shaft 119 in turn is supported in support element122. A hexagonal opening in knob 120 is part of shaft 119. Suitablebearings 121 are provided on the shafts 111, 112 and 119 for rotation ofthe various elements described. In the operation of this tool, theoperator will turn the knob 120 with a ratchet and this in turn causesrotation of the shafts 111 and 112 in the same direction, thus causingsimultaneous rotation of the threaded shafts 102 and 103 in member 57. Asimilar tool with wider-spaced shafts 111, 112 may also be used inconnection with adjustments of the primary caliper 56 in a similarfashion.

Turning now to the detail" illustrated in FIGS. 7 and 8, there is showna means for adjustment of pad wear of brake shoe 41. In thisarrangement, the guide pins 123 that support the shoe 41 extend into asleeve 124 within the caliper element 30. A threaded shaft 125 extendsinto the element and has one end 126 that engages the inner end of theguide pin 123. Thus, by rotating the shaft 125 through the knob handle127, an adjustable stop may be provided for the guide pin 123. The head127 is provided with a series of notches or teeth 128 that are engagableby the spring 129. The leaf spring 129 in turn is anchored or suitablysecured to the caliper. This spring thus provides a stop mechanism toprevent inadvertent turning of the shaft 125. Similar arrangements areprovided at opposite ends of the caliper so that simultaneousadjustments may be made to precise amounts at each end.

Referring once again to the embodiment illustrated at FIG. 4, there isshown a torque take-up arm 48' in dotted outline. The torque take-up arm48 would be used if this wheel were incorporated into the rear wheel ofa motorcycle. The torque take-up arm would not be used if the wheel wereused as the front wheel of a motorcycle. In that case, the torque thatprevents rotation of the face plate can be taken up by locking orotherwise engaging the caliper or face plate to the front fork in amanner that is generally illustrated in FIGS. 9 and 10.

Although the system describes a hydraulically operated caliperarrangement, there are no illustrations of the means by which hydraulicfluid is delivered to and taken from the caliper pistons, asconventional means well known in the art may be used for this purpose.

1 claim:

1. A combination brake and vehicle assembly including a fork with legsinterconnected at the free end by an axle comprising:

a wheel including a hub having a center core defining an aperturereceiving the axle and positioning the hub intermediate the legs of thefork;

means intermediate said core and axle for rotatably supporting said hubrelative to aid axle;

said hub including tire support means;

an annular disc having bearing surfaces on opposite sides of said disc;

means securing said disc to said hub for rotation therewith;

a pair of brake shoes each having brake pads with each of said padsaligned with one of said bearing surfaces;

calipers for holding each of said brake shoes arranged one on each sideof said disc;

caliper support means for commonly supporting said calipers extending atleast partially over and coaxial with said core;

bearing means disposed intermediate the overlapping portions of saidcore and caliper support means for supporting and permitting relativerotational movement of said core and caliper support means; and

means maintaining said caliper support means in fixed rotationalrelation to said axle.

2. A disc brake and wheel assembly as set forth in claim 1 comprisingmeans permitting limited sliding movement of said caliper support meansrelative to said core in a direction parallel to said axle.

3. A disc brake and wheel assembly as set forth in claim 2 comprisingbiasing means for urging said calipers to an inoperative position.

4. A disc brake and wheel assembly as set forth in claim 1 wherein saidcaliper support means includes an annular support means coaxial withsaid axle.

5. A disc brake and wheel assembly as set forth in claim 4 wherein saidannular support means comprises a pair of annular wall members with eachwall member supporting one of said calipers in aligned relation andmeans securing the wall members together.

6. A disc brake assembly as set forth in claim 1 wherein said tiresupport means includes a crown, said disc being secured at its outercircumference to said crown.

7. A disc brake and wheel assembly as set forth in claim 6 wherein saidcore is coaxial with said axle and said hub includes a face wallinterconnecting said core and crown.

8. A disc brake and wheel assembly as set forth in claim 7 including aface plate fixed relative to said axle, said face plate having an outerperimeter adjacent said crown, said face wall and face plate defining aspace for said brake shoe means and calipers.

9. A disc brake and wheel assembly as set forth in claim 1 includingmeans for lateral movement of said common caliper support means inresponse to application of unequal forces on opposite surfaces of saiddisc by said brake shoes.

10. A disc brake and wheel assembly as set forth in claim 9 wherein saidcalipers include a hydraulically and a non-hydraulically actuatedcaliper.

11. A disc brake and wheel assembly as set forth in claim 1 including apair of pistons for actuating each of said brake shoes and a pluralityof guide pins secured at one end to said brake shoes and extending intosaid calipers at the other end.

12. A disc brake and wheel assembly as set forth in claim 1 wherein saidmeans maintaining comprises interlocking facing splined portions of saidcaliper support means and a facing plate secured to said axle.

13. A disc brake and wheel assembly as set forth in claim 1 wherein saidcaliper support means if formed in at least two separable parts, withthe parts extending radially beyond the inner periphery of the disc andwith a portion of one part on one side and a portion of the inner parton the other side of said disc, and means locking said parts together.

14. The disc brake and wheel assembly as set forth in claim 1 whereinsaid hub defines at least in part an enclosing space, said disc andcaliper support means being supported in said space.

1. A combination brake and vehicle assembly including a fork with legsinterconnected at the free end by an axle comprising: a wheel includinga hub having a center core defining an aperture receiving the axle andpositioning the hub intermediate the legs of the fork; meansintermediate said core and axle for rotatably supporting said hubrelative to aid axle; said hub including tire support means; an anNulardisc having bearing surfaces on opposite sides of said disc; meanssecuring said disc to said hub for rotation therewith; a pair of brakeshoes each having brake pads with each of said pads aligned with one ofsaid bearing surfaces; calipers for holding each of said brake shoesarranged one on each side of said disc; caliper support means forcommonly supporting said calipers extending at least partially over andcoaxial with said core; bearing means disposed intermediate theoverlapping portions of said core and caliper support means forsupporting and permitting relative rotational movement of said core andcaliper support means; and means maintaining said caliper support meansin fixed rotational relation to said axle.
 2. A disc brake and wheelassembly as set forth in claim 1 comprising means permitting limitedsliding movement of said caliper support means relative to said core ina direction parallel to said axle.
 3. A disc brake and wheel assembly asset forth in claim 2 comprising biasing means for urging said calipersto an inoperative position.
 4. A disc brake and wheel assembly as setforth in claim 1 wherein said caliper support means includes an annularsupport means coaxial with said axle.
 5. A disc brake and wheel assemblyas set forth in claim 4 wherein said annular support means comprises apair of annular wall members with each wall member supporting one ofsaid calipers in aligned relation and means securing the wall memberstogether.
 6. A disc brake assembly as set forth in claim 1 wherein saidtire support means includes a crown, said disc being secured at itsouter circumference to said crown.
 7. A disc brake and wheel assembly asset forth in claim 6 wherein said core is coaxial with said axle andsaid hub includes a face wall interconnecting said core and crown.
 8. Adisc brake and wheel assembly as set forth in claim 7 including a faceplate fixed relative to said axle, said face plate having an outerperimeter adjacent said crown, said face wall and face plate defining aspace for said brake shoe means and calipers.
 9. A disc brake and wheelassembly as set forth in claim 1 including means for lateral movement ofsaid common caliper support means in response to application of unequalforces on opposite surfaces of said disc by said brake shoes.
 10. A discbrake and wheel assembly as set forth in claim 9 wherein said calipersinclude a hydraulically and a non-hydraulically actuated caliper.
 11. Adisc brake and wheel assembly as set forth in claim 1 including a pairof pistons for actuating each of said brake shoes and a plurality ofguide pins secured at one end to said brake shoes and extending intosaid calipers at the other end.
 12. A disc brake and wheel assembly asset forth in claim 1 wherein said means maintaining comprisesinterlocking facing splined portions of said caliper support means and afacing plate secured to said axle.
 13. A disc brake and wheel assemblyas set forth in claim 1 wherein said caliper support means if formed inat least two separable parts, with the parts extending radially beyondthe inner periphery of the disc and with a portion of one part on oneside and a portion of the inner part on the other side of said disc, andmeans locking said parts together.
 14. The disc brake and wheel assemblyas set forth in claim 1 wherein said hub defines at least in part anenclosing space, said disc and caliper support means being supported insaid space.